U.S. patent number 4,589,717 [Application Number 06/565,794] was granted by the patent office on 1986-05-20 for repeatedly operable electrical wet connector.
This patent grant is currently assigned to Schlumberger Technology Corporation. Invention is credited to Alain P. Pottier, Ralph L. Simmons, James J. Walulik.
United States Patent |
4,589,717 |
Pottier , et al. |
May 20, 1986 |
Repeatedly operable electrical wet connector
Abstract
Electrical connector assembly comprising a male and a female
connector, each having a group of electrical contacts. The bore
formed in the female connector to accommodate the male connector is
sealed by a slidable shuttle and is filled with a dielectric liquid
when the male connector is not inserted. The shuttle is subjected
to a force which tends to keep it in sealing position, and is
pushed towards the interior of the bore against the action of said
force when the male connector is inserted. The shuttle and the end
of the male connector are arranged so that the insertion of the
latter brings about a positive connection between the two. This
connection remains effective during withdrawal of the male
connector, until the shuttle reaches its sealing position.
Inventors: |
Pottier; Alain P. (Houston,
TX), Walulik; James J. (Houston, TX), Simmons; Ralph
L. (Pearland, TX) |
Assignee: |
Schlumberger Technology
Corporation (Houston, TX)
|
Family
ID: |
24260123 |
Appl.
No.: |
06/565,794 |
Filed: |
December 27, 1983 |
Current U.S.
Class: |
439/277; 439/140;
439/190; 439/359; 439/819 |
Current CPC
Class: |
H01R
13/523 (20130101); E21B 17/028 (20130101) |
Current International
Class: |
E21B
17/02 (20060101); H01R 13/523 (20060101); H01R
004/00 () |
Field of
Search: |
;339/117,94,42,75 |
References Cited
[Referenced By]
U.S. Patent Documents
Primary Examiner: Weidenfeld; Gil
Assistant Examiner: Pirlot; David L.
Claims
We claim:
1. Electrical connector assembly for effecting the connection of
groups of electrical contacts in a fluid medium, comprising:
a male connector with a cylindrical pin; and
a female connector with a bore to accommodate said pin, said female
connector comprising a sealing member slidable in the bore, a
retaining means defining an end position, in which the sealing
member closes the bore, said bore being, when the male connector is
not inserted, filled with a dielectric liquid, and means for urging
the sealing member to said sealing position;
said pin of the male connector having an end arranged for
engagement with the sealing member, said end and said sealing
member comprising means for producing a positive coupling between
the pin and the sealing member as a result of their engagement;
wherein the sealing member has a cavity and a snap ring lodged in
said cavity, and the end portion of the pin has a groove in which
said snap ring can engage to create the coupling; and
wherein the end portion of the pin includes a part having the same
diameter as the pin and a nose extending from said part, with a
radial surface joining said part and said nose, and said groove is
formed on the nose rear said radial surface; wherein the nose has a
radial hole outletting into said groove and an axial hole
connecting with said radial hole and outletting at the end of the
nose.
2. Electrical connector assembly for effecting the connection of
groups of electrical contacts in a fluid medium, comprising:
a male connection with a cylindrical pin;
a female connector with a bore to accommodate said pin, said female
connector comprising a sealing member slidable in the bore, a
retaining means defining an end position in which the sealing
member closes the bore, said bore being, when the male connector is
not inserted, filled with a dielectric liquid, and means for urging
the sealing member to said sealing position;
said pin of the male connector having an end arranged for
engagement with the sealing member, said end and said sealing
member comprising means for producing a positive coupling between
the pin and the sealing member as a result of their engagement;
wherein the female connector comprises a telescopic shuttle, said
shuttle including a first tubular piston slidable in the bore, said
sealing member being formed as the front end of said first piston,
a second tubular piston entering the first piston and resiliently
urged forward towards an abutment position, the first piston being
movable relative to the second piston between a forward sealing
position and a rear abutment position; and
a third piston mounted inside the female connector and resiliently
urged towards a front abutment position, and an axial rod connected
to this third piston and penetrating the second piston on the side
opposite the first piston, the second piston being movable relative
to said rod between a front abutment position and a rear abutment
position.
Description
This invention concerns an electrical connector assembly for
effecting repeated connections between groups of electrical
contacts in a fluid medium, and comprising a male connector and a
female connector each having a group of contacts.
A connector assembly of this type is necessary particularly more in
deviated hole logging techniques based on U.S. Pat. No. 4,349,072
and co-pending patent application Ser. No. 460,340, filed on Jan.
24, 1983, in view of establishing the electrical connection between
a logging tool placed at the end of a drill pipe and a transmission
cable connected to a surface unit.
The drilling mud which fills a well has a very high hydrostatic
pressure and is usually electrically conductive. In addition, it
contains clay or some other analogous material. It is thus
essential that the mud be prevented from entering the female
connector where the connection is to be made.
U.S. Pat. No. 3,729,699 discloses the use of a shuttle to form a
tight seal on the dielectric-fluid-filled bore of the female
connector. The pressure in this bore is maintained at a level
slightly higher than the pressure of the surrounding fluid by a
compensation device. The shuttle is held in position by a spring
and is pushed towards the interior of the bore by the male
connector when the latter is inserted to make the connection. When
the male connector is withdrawn, the shuttle is brought back to its
sealing position by the spring.
One disadvantage of known connector assemblies is that a certain
amount of dielectric fluid escapes from the bore with each
connection operation. This limits the number of consecutive
connections/disconnections that can be made.
U.S. Pat. No. 4,390,229 describes a female connector in which the
bore that is intended to accommodate the male connector is filled
with grease. According to the teaching of said patent, a loss of a
certain amount of grease upon withdrawal of the male connector is
inevitable, and that loss can be compensated by a grease supply
from a compensation bore with a pressure higher than the pressure
in the bore which accommodates the male connector.
The object of this invention is an electrical connector assembly in
which losses of dielectric material with each disconnection are
substantially eliminated and which is thus capable of a greater
number of connection and disconnection operations.
It has been found that an essential cause of the loss of dielectric
fluid is that the shuttle may fail to perfectly follow the male
connector during withdrawal. In fact, if there is a gap between the
male connector and the shuttle, the liquid filling the space
between them escapes, when the male connector is withdrawn from the
female connector.
The invention provides for an electrical connector assembly
comprising a male and a female connector, each having a group of
electrical contacts. The bore formed in the female connector to
accommodate the male connector is sealed by a slidable shuttle and
is filled with a dielectric liquid when the male connector is not
inserted. The shuttle is subjected to a force which tends to keep
it in sealing position, and is pushed towards the interior of the
bore against the action of said force when the male connector is
inserted. The shuttle and the end of the male connector are
arranged so that the insertion of the latter brings about a
positive connection between the two. This connection remains
effective during withdrawal of the male connector, until the
shuttle reaches its sealing position.
The invention will be easily understood by reading the following
description of a preferred, embodiment with reference to the
drawings.
IN THE DRAWINGS
FIG. 1 shows the male portion of the connector assembly according
to the invention.
FIGS. 2A, 2B and 2C show a longitudinal cross-section of the female
portion of the connector assembly according to the invention; FIG.
2A shows the front portion capable of accommodating the male
portion, and FIGS. 2B and 2C show the rear portion,
FIG. 3 is a detailed view of a snap ring mounted at the front end
of the female connector,
FIGS. 4, 5 and 6 are cross-sections along respectively lines 4--4,
5--5 and 6--6 of FIG. 2A,
FIG. 7 is a cross-section along line 7--7 of FIG. 2C, and
FIG. 8 illustrates a way of making an electrical connection in a
deviated borehole.
The male connector represented in FIG. 1 comprises an elongated
cylindrical pin 10 with a series of axially spaced annular
electrical contacts 11. The contacts 11 are insulated from each
other by insulator blocks 12 of same diameter. Electrical
conductors, not shown, are connected to the respective contacts 11.
The pin can be constructed in any conventional manner. For
instance, the pin may comprise a central rod supporting the
contacts and the insulator blocks, and means such as coupling pins
to hold the contacts and blocks in a proper angular position.
Conventional means, not shown, are provided at the rear end of the
male connector for its connection with an equipment such as a
transmission cable. At the front end of the male connector, there
is a piece 16 including a part 16a having the same diameter as the
insulator blocks 15 and extending in a "nose" 27 decreasing in
diameter towards the front, with a maximum diameter smaller than
that of part 16a. Near the radial shoulder 28 joining part 16a to
the nose 27 is a peripheral groove 29 formed on the nose, the role
of which will be explained below. In addition, a radial opening 30
goes through the nose at the level of the groove 29, and connects
with an axial hole 31 which outlets at the forward end of the
nose.
The female connector is represented in FIGS. 2A, 2B and 2C, with an
overlap between the figures to facilitate understanding.
The female connector has a tubular housing 40 extending throughout
its length. Inside this housing 40 are placed in succession from
front to back, a retainer 41, a series of annular insulator blocks
42, an intermediate bulkhead 43 (FIG. 2A), a thin tube 44 (FIGS.
2A, 2B and 2C) attached to the bulkhead 43 by a bayonet connection
44a, a rear bulkhead 45 fitted onto the tube 44, a spacer 46 and a
connector piece 47 (FIG. 2C). The assembly comprising these parts
abuts against an internal shoulder 48 formed at the rear end of the
housing 40 (FIG. 2C) and is held by a nut 49 screwed onto the
forward end 50 of the housing 40.
The portion represented in FIG. 2A which is intended to accommodate
the pin 10 of the male connector comprises in particular retainer
41, insulator blocks 42 and the intermediate bulkhead 43. The
insulator blocks, made of insulating material, have stepped ends 55
so that two adjacent insulator blocks present complementary parts
which fit one another.
As is clearly seen on the cross-section in FIG. 4, through-holes 56
for the passage of the conductors are formed parallel to the axis
of the plug in each insulator block 42. In addition, blind holes
57, also longitudinally oriented, are formed in each insulator
block on each side to accommodate pins for the angular positioning
of each insulator block relative to the adjacent insulator
block.
Between each pair of insulator blocks 42 is placed a contact 61
made of conductive metal. The contacts 61 comprise an internal
cylindrical portion 62 and a central external collar 63 with a
shoulder 64. The collar 63 is held between two insulator blocks 42
and has drilled holes in line with the holes 56 and 57 of the
insulator block 42, to allow passage of an alignment pin and
electrical conductors.
The set of internal surfaces of the contacts 61 defines a bore 65
with a diameter slightly larger than the external diameter of the
pin 10 of the male connector. Of course, the spacing between the
contacts 61 defined by the dimensions of the insulator block 42 is
identical to the spacing between the contacts 11 of the male
connector so as to allow simultaneous connection of the contacts 61
with the corresponding contacts 11.
Each contact 61 has on its inner surface a groove in which flexible
tabs 66 are mounted. The tabs 66 project slightly into the interior
of the bore 65 so as to ensure proper contact with the contacts 11
of the male connector.
Seals 70, generally tubular in shape, are placed between the
contacts 61. Each seal 70 includes end parts 71, 72, with an
external diameter substantially equal to the inside diameter of the
insulator blocks 42, and a central portion 73 with a smaller
diameter, which defines an annular space 74 between each seal 70
and the surrounding insulator block. Each of the end parts 71, 72
is held between the inner surface of an insulator block 42 and the
outer surface of the cylindrical portion 62 of an adjacent contact
61, with the end surface of the seal abutted against the shoulder
64 of the contact 61. The central portion 73 presents internal
corrugations 75, when seen in the axial direction. The inside
diameter of part 73, taken at mid-height of the corrugations 75, is
substantially identical to the diameter of the bore 65, so that the
crest of the corrugations projects towards the inside of the bore
65.
The insulator block 42a adjacent to the retainer 41 is connected to
the latter by pins fitted in blind holes. The retainer 41 has a
rear portion shaped like an insulator block 42 to support, along
with the adjacent insulator block 42a, the forwardmost contact 61
and seal 70.
In like manner, the insulator block 42f located at the rear of the
stack of insulator blocks, is connected to the intermediate
bulkhead 43 by pins, and as is shown in the cross-section in FIG.
5, the bulkhead 43 has openings 58 aligned with the holes 56 in the
insulator blocks for the passage of conductors.
The middle portion 80 of the retainer 41 has the same inside
diameter as the contacts 61. Its forward portion 81 has a larger
inside diameter to accommodate a seal 82, held between the middle
portion 80 and a washer 83 held by a circlip 84 inserted in a
groove in the front portion 81. The seal 82 is made of a flexible
piece with a radial wall 85 connecting an external axial wall 86 to
an internal wall 87, which is urged radially inwardly by a circular
resilient ring 88 held by the bent edge of the internal wall
87.
The bore 65 is filled with a dielectric liquid such as oil. It is
sealed in the unconnected position of the female connector
represented in FIG. 2A, by a shuttle composed in the present
embodiment of a telescopic assembly. This assembly comprises a
piston 90, the forward end of which forms a sealing member 91
having essentially the same outside diameter as the bore 65, and
the rear portion of which is a tube 92 with a slightly smaller
outside diameter, substantially equal to the diameter of the crest
of the seals 70. A second piston 95, tubular in shape, is slidable
inside tube 92. This second piston accommodates a rod 96, connected
by a pin 96a to a third piston 97 with a generally tubular shape,
which is slidably mounted in tube 44. A helicoidal spring 98 is
mounted between an inside shoulder 99 formed on a tube 99a slidably
mounted inside tube 44 and a collar 100 forming the front end of
the third piston 97. The spring 98 acts to urge the piston 97
forward into contact with the rear face of the intermediate
bulkhead 43. Another spring 101 is mounted around the front portion
102 of the rod 96, which portion has a diameter smaller than the
rest of the rod 96, between a thrust surface 103 at the front end
of the second piston 95 and a bearing surface 104 joining the front
portion 102 to the other part of the rod 96. Spring 101 acts to
urge the second piston 95 forward. The front end of the second
piston 95 has an axial opening 106 for fluid communication.
In addition, as is shown in the cross-section in FIG. 6, the third
piston 97 has on its external surface a series of longitudinal
notches 105. These notches are in communication with notches 106
formed inside the piston 97, which outlet in the space defined
between the rod 96 and the collar 100. The bore 65 is thus
connected to the space located behind the shuttle.
The sealing member 91 presents a transverse wall 110 which closes
the bore 65. Near its forward end, the sealing member 91 has an
internal peripheral groove 111 in which is lodged a flexible C-ring
112, represented on the detailed view in FIG. 3. The ring 112 is
shaped to engage the groove 29 provided at the end of the male
connector during a connection, so as to couple the male connector
to the sealing member 91 during the movement of the pin 10 inside
the bore 65 of the female connector.
The part 92 of the first piston 90 has diametrically opposed
lateral notches 114 along a good portion of its length, in which a
pin 115 attached to the front of the second piston 95, is engaged.
In the position shown in FIG. 2A, the pin 115 abuts against the
rear end wall of the notches 114, which holds the first piston 90
in the position indicated and prevents the sealing member 91 from
moving forward from its sealing position.
In like manner, a pin 116 attached to the rod 96 connected to the
third piston, is engaged in diametrically opposed notches 117
formed in the second piston 95. FIG. 2A shows pin 116 abutted
against the rear end walls of the notches 116.
Looking at FIGS. 2B and 2C showing the rear portion of the female
connector, one notes that inside of the tube 40 is placed a piston
120 which divides in a fluid-tight manner the inner spaces of the
female connector, into two chambers 121 and 122. Chamber 121
receives the piston 97 and the tube 99a and is located in the
extension of the bore 65; the fluid communication between chamber
121 and the bore 65 is, as indicated above, ensured by the notches
105 and 106 of the piston 97. Another tube 123 similar to tube 99a,
equipped like the latter with an internal shoulder is slidably
mounted inside tube 44. A spring 124 is mounted between the
internal shoulders of the two tubes 99a and 123, and another spring
125 is placed between the piston 120 and the internal shoulder of
the tube 123.
A similar arrangement is provided in chamber 122 behind the piston
120, where a tube 127 similar to tube 123 is slidably mounted. A
spring 128 resting on the inner shoulder of tube 127 acts on the
piston 120, and a spring 129 acting on the inner shoulder of tube
127 rests on a stepped washer 130 welded inside the tube 44 near
its rear end. The housing 40 has an opening 135 at the level of the
bulkhead 45, and the latter, represented in cross-section in FIG.
7, has a lateral opening 136 opposite the opening 135 and an axial
bore 137 in communication with opening 136, which in turn connects
the chamber 122 to the outside. The chamber 122 thus serves as a
pressure compensation bore, with the piston 120 transmitting the
pressure of the external fluid to the oil present in chamber 121
and in bore 65. The pressure in chamber 121 is in fact greater than
the pressure of the external fluid due to the action of the springs
128 and 129 on the piston 120. This pressure difference acts on the
sealing member 9 to keep it in the sealing position shown in FIG.
2A. A pressure differential of the order of 2 bars or more, for
example 2.5 bars, is sufficient. The springs 128 and 129 are much
stronger than springs 124 and 125 placed on the opposite side of
the piston 120.
The piston 120 has a relief valve 140 which acts to limit the
pressure in the chamber 121 to a given value, e.g. between 7 and 10
bars.
The rear bulkhead 45 has holes 141 for the passage of the
conductors, not shown, connecting the contacts 61 to the electrical
feedthroughs 142 mounted in the connection head 47. The connection
with the electrical feedthroughs 142 occurs inside the inner space
of spacer 46.
The passage of conductors from the holes 141 is supplied by the
annular space 145 between the tube 44 and the housing 40, and by
the spaces defined between the flats 146, better seen in FIG. 5,
formed on the periphery of the intermediate bulkhead 43, and the
housing 40. The holes 58 formed in the front portion of the
bulkhead 43 outlet into the spaces 146. On FIG. 4, one also notes
that the insulator blocks 42 have flats 150 on their periphery, and
radially oriented openings 151, which connect for fluid
communication the inside and outside of each insulator block 42. In
like manner, the bulkhead 43 has in its forward portion flats 152
aligned with the flats 151 of the insulator blocks 42, and a radial
opening 153 (FIG. 2A) for fluid communication between the inside of
the bulkhead 43 and the space defined between the flats 146 and the
housing 40.
This arrangement provides communication of the chamber 121, the
bore 65 which accommodates the shuttle, and the inside of tube 44,
with the annular space defined between the tube 44 and the housing
40, the holes 58 and 56 for passage of conductors, the annular
spaces 74 provided between the seals 70 and the respective
insulator blocks 42, and in the rear portion, with openings 141 and
the inner space of the spacer 46. Tightness is ensured by the seal
82 in the front of the bore 65 and by the O-ring 160 mounted on the
outside of the retainer 41, by the O-ring 161 mounted on the
compensation piston 120, by the O-ring 162 mounted on the front end
of the rear bulkhead 45 to ensure a fluid-tight connection with the
tube 44, by the seals 163 mounted on the head 45 to separate the
outlet passages of the bulkhead 45 from the space surrounding the
tube 44 and from the openings 141, and by the connector head
47.
FIG. B illustrates, in a non-limiting manner, an example of
utilization and a suitable technique for bringing into engagement
the male connector and the female connector in a highly deviated
borehole. Such a technique is described in copending patent
application Ser. No. 460,340 filed Jan. 24, 1983, assigned to the
assignee of the present application, and which is incorporated
herein by reference.
The female connector is shown as reference numeral 200 in FIG. 8,
the only portion shown being its forward end. The female connector
is connected to a logging tool 201 releasably secured at the bottom
end of a drill pipe 202. The female connector is mounted inside the
bottom end of a stinger tubing 203 disposed inside the drill pipe
202 and secured to the logging tool 201.
The male connector 205 is suspended from the transmission cable 206
which it is intended to connect to the logging tool 201. A dual
locomotive device including an outer locomotive 207 and an inner
locomotive 208 is used to pump down the male connector into
engagement with the female connector 200. In a first step of the
descent the two locomotives form a unit with the male connector,
which unit is pumped down through the drill pipe by the action of
the outer locomotive 207. It is to be noted that instead of this
arrangement, the male connector can be attached to the logging tool
and the female connector suspended from the cable. The following
description would remain true except that the movable part,
connected to the locomotive, would be the female connector and not
the male connector.
When the latter engages the upper end of the stinger tubing 203,
the continuing pumping brings about the separation of the
locomotives. The inner locomotive together with the male connector
is pumped down further through the stinger tubing. It should be
noted that the stinger tubing 203 has an inwardly projecting
portion 209 forming on one side an abutment surface engaged by the
female connector and on the other side an abutment surface intended
for engagement by the male connector and thus defining the final
connection position of the male connector. Nevertheless, other
means could be used to define the final position of the male
connector, for instance there could be provided abutment surfaces
respectively on the male and the female connector, which surfaces
would engage each other directly.
The operation of the connector assembly will now be described in
detail.
When the male connector is brought into contact with the female
connector, the nose 27 of the pin 10 enters the opening of the
sealing member 91 until the shoulder 28 at the front of the pin
engages the annular end surface of the sealing member 91. Just
before the contact occurs, the snap ring 112 engages in the groove
29 formed on the nose of the pin 10. As the nose 27 moves into the
sealing member, the fluid, i.e. the drilling mud in the above
described situation, present in the cavity of the sealing member is
expelled through the axial hole 31 and the radial hole 30.
Continued movement of the male connector pushes the sealing member
91 and thus the piston 90 towards the inside (to the rear, per the
foregoing definitions) against the action of the oil pressure in
the bore 65. The pin 10 replaces the sealing member 91 in the
cooperation with the seal 82 to maintain the tightness of the bore
65 from the external fluid. In the first phase, only the piston 90
moves back. When the pin 115 of the second piston 95 comes into
contact with the front end of the notches 114, the second piston 95
is also moved back against the action of the spring 101. Then, when
pin 116 connected to the third piston 97 reaches the front end of
the notches 117, the third piston is in turn pushed back against
the action of the spring 98. Springs 124 and 125 are then
compressed until tubes 99a and 123 are abutted.
In addition, the insertion of the pin 10 into the bore 65 expels
the oil out of the latter and moves the piston 120 back since the
volume of the oil bore must remain essentially constant. The
springs 128, 129 are further compressed by this piston movement and
thus the force exerted on the piston 120 by the springs is
substantially increased and with it the pressure of the oil in
chamber 121.
The rise in the oil pressure, especially in the annular spaces 74
surrounding the seals 70 results in a considerable increase in the
contact pressure exerted by the seals 70 on the pin 10. Due to this
reinforced action of the seals 70, any films of drilling mud
remaining on the pin 10 are broken thus eliminating the risk of
short-circuits between adjacent contacts due to the presence of
such films (as drilling fluid is generally a conductor). The relief
valve 140 installed in the piston 120 prevents the establishment of
an excessive pressure at this point.
The insertion movement of the male connector ends when the latter
comes into contact with the projecting portion 209 of the stinger
tubing. In this relative position of the male and female
connectors, the contacts 11 and 61 are exactly opposite one another
and the electrical connection is made.
At this point, a logging operation can be carried out, in
accordance with the technique described in U.S. Pat. No. 4,349,072
or the above-mentioned patent application. The logging tool 201 is
released and the stinger tubing together with the logging tool is
pumped out of the drill pipe, until the upper end of the stinger
tubing engages a stop on the drill pipe. Then the ensemble is
returned to its initial position inside the drill pipe by pulling
on the transmission cable, and the logging measurements are
produced during that return motion.
To disconnect, the male connector is withdrawn from the bore 65 by
pulling on the cable. During withdrawal, the oil pressure in
chamber 121 gradually decreases. The sealing member 91 is forced to
allow the male connector because of the pressure differential and
of their mutual coupling created by the engagement of the snap ring
112 in the groove 29. This eliminates any risk of a gap between
them during withdrawal. If such a gas was allowed to occur, the
resulting free space would be occupied by the oil and thus a
certain quantity of oil would escape when the male connector is
fully withdrawn.
Continued movement of the withdrawing male connector returns the
shuttle to the position shown in FIG. 2A, according to a process
inverse of that initiated by the insertion of the pin 10. When the
sealing member 91 has reached its end position, defined by the
abutting of pin 115 against the end of the notches 114, the
withdrawal of the male connector causes the disengagement of the
snap ring 112 from the groove 29, thus freeing the male
connector.
It should further be noted that with the device described, the
assembly of the female connector is simplified. First the front
portion including retainer 41, insulator blocks 42 and the
intermediate bulkhead 43, contacts 61 and seals 70 is preassembled,
and the conductors are threaded through the appropriate holes. The
rear portion is also pre-assembled, i.e. essentially the tube 44
and the elements it accommodates, the washer 130 secured to the
tube serving as a retainer against the springs. The telescopic
shuttle is inserted in the bore 65 defined by the front portion,
and then the tube 44 is attached to the bulkhead 43 by means of the
bayonet connection 44a. The electrical conductors can be taped or
otherwise attached to the outer surface of the tube 44. They are
passed through the openings 141 in the head 45, the forward end of
which has first been inserted into the tube 44, and they are
attached to the electrical feedthroughs 142, for which purpose the
spacer 46 is provided with a side opening. The sub-assembly thus
formed is inserted inside the housing 40 until the head 47 comes
into contact with the shoulder 48 at the rear end of the housing
40, and the nut 49 is then screwed onto its forward end.
A cylindrical fill pin with the same shape and size as the pin 10
of the male connector and which has an axial passage outletting to
its forward end, is used to fill the chamber 121. This pin is
inserted in the female connector to push the shuttle and the piston
120 back into their respective connection position. At this point,
the axial passage is connected to a vacuum pump to evacuate the air
from the female connector, then to an oil pump. The oil is pumped
into the female connector until the pressure reaches the set point
of relief valve 140. Pumping is then stopped and the fill pin is
removed. The shuttle and the piston 120 return to their position
shown in FIG. 2A, and since the springs 128, 129 are less
compressed, the oil pressure falls to a relative value of about 2.5
bars, sufficient, however, to keep the sealing member 91 firmly in
the sealing position represented in FIG. 2A.
* * * * *